Superlattice quantum well thermoelectric material

• US 5,436,467 A
• Filed: 01/24/1994
• Issued: 07/25/1995
• Est. Priority Date: 01/24/1994
• Status: Expired due to Term

• Current Assignee: HI-Z Technology, Inc.
• Original Assignee: HI-Z Technology, Inc.
• Inventors: Elsner, Norbert B., Ghamaty, Saeid
• Primary Examiner(s): Saadat, Mahshid D.
• Application Number:
  US08/185,562
• Time in Patent Office: 547 Days
• Field of Search: 257/613, 257/614, 257/616, 257/625, 257/930, 257/15, 62/3.2, 136/203
• US Class Current: 257/15
• CPC Class Codes: H01L 29/16 including, apart from doping materials or other impurities, only elements of Group IV of the Periodic Table
• CPC Class Codes: H10N 10/855 comprising compounds containing boron, carbon, oxygen or nitrogen
• CPC Class Codes: Y10S 257/93 Thermoelectric, e.g. peltier effect cooling

Abstract

A multi-layer superlattice quantum well thermoelectric material using materials for the layers having the same crystalline structure. A preferred embodiment is a superlattice of Si and SiGe, both of which have a cubic structure. Another preferred embodiment is a superlattice of B-C alloys, the layers of which would be different stoichometric forms of B-C but in all cases the crystalline structure would be alpha rhombohedral.

Claims

1. A thermoelectric material comprised of:

a plurality of alternating layers of at least two different semiconducting materials, one of said material defining a barrier material and another of said materials defining a conducting material,

said barrier material and said conducting material having the same crystalline structure,

said barrier material and said conducting material having band gaps, the band gap of said barrier material being higher than the band gap of said conducting material,

said conducting material being doped to create conducting properties,

said layer arrangement of said at least two different materials creating a superlattice and quantum wells within said layers of said conducting material.

2. A thermoelectric material as in claim 1 wherein said crystal structure is cubic.

3. A thermoelectric material as in claim 2 wherein said barrier material is silicon and said conducting material is silicon germanium.

4. A thermoelectric material as in claim 3 wherein the concentration of germanium in said conducting material is between 10 percent and 40 percent.

5. A thermoelectric material as in claim 4 wherein said conducting material is doped with phosphorous.

6. A thermoelectric material as in claim 4 wherein said conducting material is doped with boron.

7. A thermoelectric material as in claim 1 wherein said crystal structure is alpha rhombohedral.

8. A thermoelectric material as in claim 4 wherein at least one of said two different materials is an alloy of boron and carbon.

9. A thermoelectric material as in claim 1 wherein at least two of said at least two different materials are both alloys of boron and carbon.

10. A thermoelectric material comprised of:

at least 100 alternating layers of at least two different semiconducting materials, one of said materials defining a barrier material and another of said materials defining a conducting material, each layer of at least 50 layers of said conducting material being less than 100 Å

thick,

said barrier material and said conducting material having the same crystalline structure,

said barrier material and said conducting material having band gaps, the band gap of said barrier material being higher than the band gap of said conducting material,

said conducting material being doped to create conducting properties,

said layer arrangement of said at least two different materials creating a superlattice and quantum wells within said layers of said conducting material.